Chapter 14. Lambda Core [Black Mesa]
Kill the Vortigaunts and large monsters that appear. Once we clear the hall, the scientist upstairs will open the door for us.
The scientists ask us to start the reactor to create a new portal to fix the situation. In the next room, another scientist will give us a new weapon—a gluon gun. We test it out, grab some ammo and first aid kits. Continue down the hallway to the left, enter the elevator through the glass doors, and go down.
We kill the small monsters. We move along the corridor, and behind a large red-and-white device we find a battery, an underbarrel grenade, and crossbow arrows.
We enter the large room, climb the stairs to the third floor, and take the elevator down one floor. We continue along the corridor, turn into the room on the left, and climb over the barricades. On the second floor, we descend into the hatch, press the lever there, and continue through the opened doors.
We find ourselves in a large but empty reservoir. We descend the stairs to the bottom of the reservoir. At the bottom, press the green button on the wall. We return to the elevator and return to the top. On one of the walls, near the control panels, we find and press the switch. Water will begin to fill the reservoir. We can return to the central room.
We pass through the rubble. We approach the reservoir and jump into the water. We find a button underwater, press it, and stand on a small moving platform; the platform lifts us higher. We enter the door and go along the corridor.
We find ourselves in an empty reservoir. Press the button on the wall. We take the elevator up. Activate the lever near the control panel, which will cause the reservoir to begin filling with water. Return to the central room above.
We enter the central reservoir of the cooling system through the left corridor. Many Vortigaunts and large monsters will appear here; deal with them all. In the tower on the central yellow bridge, you can get a first aid kit and a battery. We jump into the water and swim through the side underwater tunnel in the center.
We'll reach the Lambda Complex's core. We'll climb higher and higher up the stairs, fighting off the emerging Vortigaunts.
On the 5th floor, press the lever, which will activate the central installation and emit powerful red lasers. We'll continue climbing, dodging the lasers; they always hit the same spot.
After exiting the central shaft, we'll climb the stairs and enter the guard's room. Restore your health using the first aid kit and charger, and collect some ammo. Continue down the corridor.
Continue down the corridor to the right. You can go through the door on the left to practice using portals. You can only enter the yellow portals, after which we instantly find ourselves where the green portal is. Further down the corridor, you can go down the elevator to see a diagram of the Lambda complex core, and see it in person through the glass. We return to the top and enter the last door.
1. Approach the yellow teleporter on the stairs and look through the window. When a moving platform passes under the green portal, enter the yellow portal.
2. From the platform, jump into gate 02 (do not enter the portal yet).
3. Look up; when a platform passes under the green portal above, enter the yellow portal. After teleporting, quickly sit down to avoid hitting the pipe.
4. Jump into gate 04 (do not enter the portal yet).
5. Look up in the right corner. When a platform passes under the green portal above, enter the yellow portal in the center.
6. From the platform, jump into gate 07.
7. You'll find yourself in a separate room. Here, jump onto the middle ring, which rises and descends. From the ring, jump across the platforms to door 01, press the button, then to door 02, press another button on them. After this, a path to the portal will open in the center; jump across and teleport.
We visit the scientists, listen to them, restore health, collect a full arsenal of weapons, and take the rocket pack (Long Jump Module). We proceed through the white chamber that opens.
We enter a room with a large teleportation device. One of the scientists will activate it, and we need to fend off the flying monsters that appear. It's best to use the gluon cannon or revolver.
After a while, the portal in the center will open, and a bridge will extend towards it. Run along the bridge, jump, and teleport to the alien world— Xen.